Honzuki no Gekokujou: Shisho ni Naru Tame ni wa Shudan wo Erandeiraremasen OVA

本好きの下剋上 司書になるためには手段を選んでいられません OVA

Side Story #1: Eustachius's Incognito Operation Downtown
The head priest wants more information on Myne, and so he sends two of his aides, Eckhard and Eustachius, to investigate her.

Side Story #2: Visiting Missus Corinna
Effa and Tuuli find themselves having to accompany Myne to Corinna's residence, because she wants to take a look at the outfit Myne wore for her baptism.

Note: This two-part OVA was bundled with Part 5 Volume 1 of the LN. The OVA consist of two side stories, the first adapts a chapter from Part 3 Volume 2 of the LN, and the second adapts a chapter from Part 1 Volume 3 of the LN. Both side stories chronologically happen at the end of Part 1 of the LN.

(Source: AniList.co)